Shire Receives INTUNIV(TM) Paragraph IV Notice Letter

Impax is the Fifth Paragraph IV Filer Against INTUNIV

DUBLIN, November 1, 2010 - Shire plc (LSE: SHP, NASDAQ: SHPGY), the global specialty
biopharmaceutical company, announces that it has received a Paragraph IV
Notice Letter from Impax Laboratories, Inc. ("Impax") advising of the filing
of an Abbreviated New Drug Application ("ANDA") for a generic version of
Shire's 4 mg guanfacine hydrochloride extended release tablet, INTUNIV(TM).
Shire had previously reported in March 2010 of the receipt of a Paragraph IV
Letter from Teva Pharmaceuticals USA, Inc., and in April 2010 of a Paragraph
IV Letters from Actavis Elizabeth LLC and Anchen Pharmaceuticals, Inc., both
regarding ANDAs for generic versions of Shire's 1 mg, 2 mg, 3 mg, and 4 mg
guanfacine hydrochloride extended release tablets. In October 2010, Shire
reported the receipt of a Paragraph IV Letter from Watson Laboratories, Inc.
regarding an ANDA for a generic version of Shire's 4 mg guanfacine
hydrochloride extended release tablets.

INTUNIV is protected by three FDA Orange Book listed patents: U.S. Patent
No. 5,854,290 ("the '290 patent") titled Use of Guanfacine in the Treatment
of Behavioral Disorders; U.S. Patent No. 6,287,599 ("the '599 patent") and
U.S. Patent No. 6,811,794 ("the '794 patent") both titled Sustained Release
Pharmaceutical Dosage Forms with Minimized pH Dependent Dissolution Profiles.
The three patents expire in 2015, 2020 and 2022, respectfully.

Shire is currently reviewing the details of Impax's Paragraph IV Notice
Letter which was directed to the '290, '599 and '794 patents.

The Hatch-Waxman exclusivity period for INTUNIV runs until September 2,
2012 therefore, ANDA for generic versions of INTUNIV cannot be approved prior
to the end of that exclusivity period.

Under the Hatch-Waxman Act, Shire has 45 days from the receipt of the
Notice Letter to determine if it will file a patent infringement suit. If
Shire brings suit pursuant to the Hatch Waxman regulations, a stay of
approval of up to 30-months will be imposed by the FDA on Impax's ANDA.

Notes to editors

SHIRE PLC

Shire's strategic goal is to become the leading specialty
biopharmaceutical company that focuses on meeting the needs of the specialist
physician. Shire focuses its business on attention deficit hyperactivity
disorder (ADHD), human genetic therapies (HGT) and gastrointestinal (GI)
diseases as well as opportunities in other therapeutic areas to the extent
they arise through acquisitions. Shire's in-licensing, merger and acquisition
efforts are focused on products in specialist markets with strong
intellectual property protection and global rights. Shire believes that a
carefully selected and balanced portfolio of products with strategically
aligned and relatively small-scale sales forces will deliver strong results.

For further information on Shire, please visit the Company's website:
www.shire.com.

"SAFE HARBOR" STATEMENT UNDER THE PRIVATE SECURITIES LITIGATION REFORM
ACT OF 1995

Statements included herein that are not historical facts are
forward-looking statements. Such forward-looking statements involve a number
of risks and uncertainties and are subject to change at any time. In the
event such risks or uncertainties materialize, the Company's results could be
materially adversely affected. The risks and uncertainties include, but are
not limited to, risks associated with: the inherent uncertainty of research,
development, approval, reimbursement, manufacturing and commercialization of
the Company's Specialty Pharmaceutical and Human Genetic Therapies products,
as well as the ability to secure and integrate new products for
commercialization and/or development; government regulation of the Company's
products; the Company's ability to manufacture its products in sufficient
quantities to meet demand; the impact of competitive therapies on the
Company's products; the Company's ability to register, maintain and enforce
patents and other intellectual property rights relating to its products; the
Company's ability to obtain and maintain government and other third-party
reimbursement for its products; and other risks and uncertainties detailed
from time to time in the Company's filings with the Securities and Exchange
Commission.

    For further information please contact:

    Investor Relations  Eric Rojas (erojas@shire.com)       +1-781-482-0999

    Media               Jessica Mann (jmann@shire.com)      +44-1256-894-280
                        Matthew Cabrey (mcabrey@shire.com)  +1-484-595-8248

For further information please contact: Investor Relations: Eric Rojas (erojas at shire.com), +1-781-482-0999. Media: Jessica Mann (jmann at shire.com), +44-1256-894-280; Matthew Cabrey (mcabrey at shire.com), +1-484-595-8248.